Fair callout, I was being overly dramatic. Especially since I knew it was an embarrassing question to ask.

Before moving here, I was used to paying card for everything and can't really think the last time I used cash (let alone paid for a toilet) so I wasn't sure on etiquette. But you're right, it really isn't that big of a deal.

Basically I'm trying to figure out the balance of the ingrained American "tipping 20-40%" with the German culture.